diff options
| -rw-r--r-- | arch/x86/kernel/hpet.c | 65 |
1 files changed, 31 insertions, 34 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index 71533f53fa1d..8c57dbf15e3b 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -809,38 +809,6 @@ static struct clocksource clocksource_hpet = { .resume = hpet_resume_counter, }; -static int __init hpet_clocksource_register(void) -{ - u64 start, now; - u64 t1; - - /* Start the counter */ - hpet_restart_counter(); - - /* Verify whether hpet counter works */ - t1 = hpet_readl(HPET_COUNTER); - start = rdtsc(); - - /* - * We don't know the TSC frequency yet, but waiting for - * 200000 TSC cycles is safe: - * 4 GHz == 50us - * 1 GHz == 200us - */ - do { - rep_nop(); - now = rdtsc(); - } while ((now - start) < 200000UL); - - if (t1 == hpet_readl(HPET_COUNTER)) { - pr_warn("Counter not counting. HPET disabled\n"); - return -ENODEV; - } - - clocksource_register_hz(&clocksource_hpet, (u32)hpet_freq); - return 0; -} - /* * AMD SB700 based systems with spread spectrum enabled use a SMM based * HPET emulation to provide proper frequency setting. @@ -869,6 +837,32 @@ static bool __init hpet_cfg_working(void) return false; } +static bool __init hpet_counting(void) +{ + u64 start, now, t1; + + hpet_restart_counter(); + + t1 = hpet_readl(HPET_COUNTER); + start = rdtsc(); + + /* + * We don't know the TSC frequency yet, but waiting for + * 200000 TSC cycles is safe: + * 4 GHz == 50us + * 1 GHz == 200us + */ + do { + rep_nop(); + now = rdtsc(); + } while ((now - start) < 200000UL); + + if (t1 == hpet_readl(HPET_COUNTER)) { + pr_warn("Counter not counting. HPET disabled\n"); + return false; + } + return true; +} /** * hpet_enable - Try to setup the HPET timer. Returns 1 on success. @@ -890,6 +884,10 @@ int __init hpet_enable(void) if (!hpet_cfg_working()) goto out_nohpet; + /* Validate that the counter is counting */ + if (!hpet_counting()) + goto out_nohpet; + /* * Read the period and check for a sane value: */ @@ -948,8 +946,7 @@ int __init hpet_enable(void) } hpet_print_config(); - if (hpet_clocksource_register()) - goto out_nohpet; + clocksource_register_hz(&clocksource_hpet, (u32)hpet_freq); if (id & HPET_ID_LEGSUP) { hpet_legacy_clockevent_register(); |